Web-Based Self-Paced Virtual Prototyping Tutorials

1. Web-Based Self-Paced Virtual Prototyping Tutorials Rajan Bhatt Chin Pei Tang Automation, Robotics & Mechatronics Laboratory (ARM Lab) Supervisor: Venkat Krovi

2. VP in Engineering • Virtual Prototyping (VP) – Simulation-Based Design (SBD) – has gained popularity in most engineering design processes. • Significant demand from industry for students trained in this methodology. • However, not much room in engineering curriculum permits widespread adoption in the lecture-based classroom currently. http://www.dynamicdesignermotion.com/

3. Tutorials Goal Develop a series of web-based self-paced VP tutorials, permit the students to: • interactively explore the process of creating engineering analysis models in integrated VP environment; • develop skills forinteractive SBD of models; and • develop engineering judgment by interactive exploration of a spectrum of exercises.

4. Criteria met? Conventional Approach $$$ 1. Conceptual Design 2. Build Physical Prototype 3. Measure Performance and Test No 4. Modify Physical Prototype Yes 5. Manufacture Product

5. 1. Conceptual Design 2. Build Virtual Prototype 3. Measure Performance and Test by Simulation No 4. Refine Virtual Prototype Criteria met? Criteria met? Yes 5. Build Physical Prototype 6. Test Physically No Yes 7. Manufacture Product Less $ !!! Virtual Prototyping

6. Why VP now? • The availability of low-cost PC based parametric simulation and analysis tools. • The capability of integrating multiple functionalities into a unified environment. http://www.dynamicdesignermotion.com/

7. Issues • Limited room in current engineering curriculum. • Considerable amount of hands-on practice is necessary to effectively learn the tools. • Development of tutorials targeted to MAE412: Machines & Mechanisms II.

8. Need for Our Tutorials • Our students do not have experience with • Operating the CAD application software • Analyzing the resulting output • Factors impeding wide-spread adoption of existing tutorials to directly augment the engineering class: • The vendors’ tutorials may be targeted at more experienced user. • The overall complexity and time required to learn these tools. • Lack of linkage (to the course material)

9. Traditional Approach • Concepts and ideas of mechanism theory are delivered in class-room based lecture. • Mathematical formulation are emphasized. • Approach limits the complexity of the model handled.

10. VP Approach VP allows us to: • Quantitatively analyze complex mechanisms and their motions. • Interactively examine many different alternatives • Interactively visualize motions of the mechanism Grashof Non-Grashof However, is a “black box” approach

11. Grashof Non-Grashof Our Philosophy Link traditional theoretical approach and VP approach Link Traditional Approach VP Approach

12. Implementation Phase 1 Get familiarized to the tools Understand various mechanisms Phase 2 Develop engineering judgment skills Introduce VP into engineering design process Phase 3 Build physical systems based on SBD

13. Phase I • Analytical Approach • Idealize by making assumptions • Draw FBD • Develop and solve EOMs • VP Approach • Convert to Virtual Prototype • Simulate and visualize motion • Plot and analyze the results “A pendulum of length of L with a bob of mass m is pulled back to reach an initial angle of o from the vertical reference line and then released from rest. Determine the velocity of the mass at the lowest point of its swing.”

14. Phase II • Analytical Approach • Apply Grashof criterion • Limiting position by geometric or analytic methods • Iterative design process is tedious • VP Approach • Visualize by giving motion • Limiting position from the graphs plotted • Iteratively design sprinkler for desired range of operation. “Given the link lengths of a four-bar lawn sprinkler mechanism: • Analyze its rotatability and its limiting position. • Given the values of the angles θ1 and θ2, determine the angles θ3 and θ4. • If Joint 2 is rotating at an angular velocity of ω2 and an angular acceleration of α2, determine the angular velocities and accelerations of the other joints. • Given the mass and moment of inertia of the links, determine the actuation torque τ4 required at joint 4 in order to drive the system at the required velocity and acceleration.”

15. Click to play Phase III Design a mechanism to launch a squash ball • the furthest distance • Precision shooting into a basket of specified dimensions Limitations on actuator sizes, overall dimensions and material were also imposed. Students were required to follow previously mentioned creation, testing, and refinement cycle.

16. Click to play Phase III

17. Conclusion • Bridging the gap between the conventional theoretical approach and newer virtual prototyping approach. • Quantitative Assessment/Evaluation of effectiveness of the tutorials needs to be pursued.